"He'd actually had three years nearly at the front, as a gunner, in very heavy firing consistently in France, Flanders, and Russia.

"But we know from other people's statements that this bloke would sit in the trench just before and after grenades were biffing around the place and actually drawing.

"You can almost smell the putrid flesh through his paint.

"They show the horrendous physical conditions of the trenches. They show blokes eating their supper in a trench, leaning against the dead body of one mate and the skeleton of another, embedded literally into the wall of the trench, munching at his supper as though nothing was happening. You could say he was painting it out of his system. Painting it not just to forget...but also painting it because he wanted people to know what the effects of war were like.

"After the war, he's actually painting the effects of the war on human bodies.

"Really, the psychological effect as well - and the mental devastation on the human being, but he images it in the flesh, and it's really crude, deliberately grotesque manner, because he really wants to shock people. The effects of war are when you see somebody with half their faced scarred away, walking down the street, and you try and look away.

"And once the war is over, particularly the prostitute and the war cripple, if you like, are the two most trenchant ways in which you could actually imagine on a human body the horrors and degradation of the war. So he implies that the brutalizing done to you, whether it's as soldier or as a prostitute in that war was savage and real."